std::inout_ptr_t<Smart,Pointer,Args...>::~inout_ptr_t

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~inout_ptr_t();
(since C++23)

Resets the adapted Smart object by the value of modified Pointer object (or the void* object if operator void**() has been called) and the captured arguments. release() may be called on the adapted Smart object if it is not called by the constructor.

Let

  • s denotes the adapted Smart object,
  • args... denotes the captured arguments,
  • p denotes the value of stored Pointer, or static_cast<Pointer>(*operator void**()) if operator void** has been called,
  • SP be
    • Smart::pointer, if it is valid and denotes a type, otherwise,
    • Smart::element_type*, if Smart::element_type is valid and denotes a type, otherwise,
    • std::pointer_traits<Smart>::element_type*, if std::pointer_traits<Smart>::element_type is valid and denotes a type, otherwise,
    • Pointer,
  • /*do-release*/ denotes s.release() if the constructor does not call release(), empty otherwise.

If Smart is a pointer type, the destructor performs

s = static_cast<Smart>(p);, and the program is ill-formed if sizeof...(Args) > 0;

otherwise, if s.reset(static_cast<SP>(p), std::forward<Args>(args)...) is well-formed, the destructor performs

/*do-release*/; if (p) { s.reset(static_cast<SP>(p), std::forward<Args>(args)...); };

otherwise, if std::is_constructible_v<Smart, SP, Args...> is true, the destructor performs

/*do-release*/; if (p) { s = Smart(static_cast<SP>(p), std::forward<Args>(args)...); };

otherwise, the program is ill-formed.

Notes

The implementation may allocate the storage for the data structure needed for Smart (e.g. a control block) on construction, in order to leave non-throwing works to the destructor.

Arguments captured by value are destroyed after resetting.

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 3897 C++23 the destructor did not update a raw pointer to the null value it does